A centrifugal sifter, also known as a rotary sieve, is a type of industrial machine used to screen and separate powdered or granular materials.
How it Works
Based on the principle of centrifugal forces, the centrifugal sifter efficiently separates particles based on size. Material is fed into the sifter, where internal components (like paddles or screws) rotate at high speed within a cylindrical screen. This rotation generates centrifugal force, which pushes the material against the screen.
- Particles smaller than the screen mesh pass through and are discharged as the "undersize" or "in-spec" product.
- Larger particles and foreign contaminants that cannot pass through the screen are propelled along the screen surface towards a separate outlet, discharged as "oversize" or "rejects".
Key Features and Purpose
Centrifugal sifters are widely used in various industries, including food, pharmaceutical, chemical, and mining, for tasks such as:
- Scalping: Removing oversized particles or foreign objects from a product stream.
- Fines Removal: Separating fine particles from coarser material.
- Product Classification: Sorting powders or granules into different size ranges.
- Deagglomeration: Breaking down soft lumps or agglomerates.
They are known for their high throughput, compact design, and ability to handle difficult-to-screen materials that might blind traditional vibratory screens.
Typical Configuration
A standard centrifugal sifter setup includes:
- One Inlet: Where the un-sifted material enters.
- Two Outlets:
- One for the undersize (in-spec) powder.
- One for the oversized particles or foreign contaminants.
This two-outlet system ensures efficient separation of accepted product from waste or undesirable components.
